1. Field of the Invention
The present invention relates to a method for setting communication parameters that are used for communication among a plurality of communication devices.
2. Description of the Related Art
In a case where communication is performed among wireless communication devices through a wireless local area network (LAN) based on the Institute of Electrical and Electronics Engineers (IEEE) 802.11, the following communication parameters may be required to be set in the wireless communication devices: for example, service set identifiers (SSIDs), authentication methods [None/Wireless fidelity Protected Access-PreShared Key (WPA-PSK)/WPA-Remote Authentication Dial-In User Service (RADIUS)], user identifications (IDs) and corresponding passwords, encryption methods [None/Wired Equivalent Privacy (WEP)/Temporal Key Integrity Protocol (TKIP)/Advanced Encryption Standard (AES)], encryption keys, and operation modes [Ad-hoc/Infrastructure].
When the aforementioned communication parameters are set in a wireless LAN access point (AP), a personal computer (PC) may be connected to the AP through wiring, for example, a wired LAN or a Universal Serial Bus (USB) cable, and the user interface of the PC may be used. The following two methods for setting communication parameters in an AP through a PC exist.
In a first method, a web page for setting communication parameters is provided in an AP in advance. Then, a web server (a hypertext transport protocol (HTTP) server) is activated, and a user activates a web browser on a PC and accesses the web page for setting communication parameters to set communication parameters in the AP. This method is used mainly when a PC is connected to an AP via a wired LAN.
In a second method, a user activates a wizard for setting communication parameters on a PC and inputs communication parameters. Then, the input communication parameters are sent to an AP. This method is used mainly when a PC is directly connected to an AP via, for example, a cable.
When communication parameters are set for a wireless LAN card that is inserted into a card slot of a PC or a wireless LAN unit that is built in a PC, a user activates a wizard for setting communication parameters on a PC and inputs communication parameters to be set.
When a wireless LAN card is inserted into a card slot of a device other than a PC, for example, a digital camera or a printer, or when a wireless LAN unit is built in the device, the user interface of the device may be used to input communication parameters, as in the case of a PC.
FIG. 18 shows an exemplary user interface of a digital camera for setting communication parameters. In FIG. 18, reference numbers 1801, 1802, 1803, 1804, and 1805 denote a digital camera, a liquid crystal display, a cursor key, a menu key, and a selection key, respectively. The user of the digital camera 1801 sets communication parameters for the digital camera 1801. The user may confirm the communication parameters on the liquid crystal display 1802 by using the cursor key 1803, the menu key 1804, and the selection key 1805 of the user interface.
In this case, when the user uses the aforementioned user interface to input communication parameters, it may be cumbersome for the user to set communication parameters. In particular, when the user inputs character strings such as an SSID or an encryption key, it may be difficult for the user to set communication parameters using only the cursor key 1803, the menu key 1804, and the selection key 1805.
Thus, when communication parameters are set in a device other than a PC, for example, a digital camera, in many cases, the device is connected to a PC so that the user interface of the PC is used to set the communication parameters. In this case, the device is connected to the PC through, for example, a wired LAN or a USB cable. However, this method for setting communication parameters has a disadvantage in that communication parameters may not be set without a PC.
Thus, recently, methods for setting communication parameters in which specified devices are directly connected to each other have been developed.
For example, a method for setting up a second communication unit (wireless communication) by using a first communication unit (contact-type wire communication) is disclosed in United States Patent Application No. 20020147819 (Japanese Patent Laid-Open No. 2002-359623).
Moreover, a method for sending information that is required for communication through a wireless connection path to an opposite terminal using a wire communication unit is disclosed in Japanese Patent Laid-Open No. 2002-312155. A method for performing switching between communication through a wired connection path and communication through a wireless connection path when attachment or detachment of a terminal has been detected is also disclosed in Japanese Patent Laid-Open No. 2002-312155.
In the methods disclosed in the aforementioned patent documents, devices are connected to each other through wire communication to set communication parameters. These methods have a disadvantage in that devices need to be connected to each other with a cable and thus the operation may be cumbersome. In view of this disadvantage, methods for setting communication parameters by using wireless communication have been developed.
Such methods are disclosed in, for example, United States Patent Application Nos. 20040076300 and 20050201557.
However, when communication parameters are set by using wireless communication, the following two cases need to be prevented from occurring: a first case where communication parameters are intercepted by an eavesdropping attacker and a second case where communication parameters are set in a device that is not specified or a device with which someone (a brute force attacker) intends to carry out an illegal activity because it is difficult to determine a device that needs to be set up.
In the methods disclosed in United States Patent Application Nos. 20040076300 and 20050201557, the range of radio waves made available for communication is narrowed down at the time of setting so that the range becomes narrower than a normal communication range, and thus the aforementioned two cases may be prevented from occurring.
FIG. 19 shows a range within which communication parameters can be set for devices. In FIG. 19, reference number 101 denotes a wireless access point, reference numbers and letters 102A and 102B denote wireless terminals that communicate with the wireless access point 101 through air, and reference letters AR and MR denote a normal wireless communication area and a wireless communication area for setting, respectively.
Communication parameters can be set for the wireless terminal 102A, which is used in the wireless communication area MR for setting, without the wireless terminal 102A being moved from the current area, as shown in FIG. 19. However, when communication parameters are set for the wireless terminal 102B, which is used in an area outside the wireless communication area MR for setting, the wireless terminal 102B needs to be temporarily moved into the wireless communication area MR for setting. Then, the wireless terminal 102B needs to be moved back into the original area, in which the wireless terminal 102B is used in a normal operation, after the communication parameters have been set.
When the wireless terminal 102B is a terminal that can be readily moved, for example, a notebook PC or a digital camera, the setting operation may not be cumbersome for the user. In contrast, when the wireless terminal 102B is a terminal that cannot be readily moved, for example, a desktop PC or a printer, the setting operation may be very cumbersome for the user.